Should You Worry?
When your home's duct-work starts banging or popping, it can feel like your walls are vibrating. But those sudden sounds are more than just a nuisance; they may be a sign that something is wrong with your HVAC system. From pressure imbalances to dirty air filters, there are several common reasons why duct-work bangs
FILTERS:
One of the most common culprits behind loud ducts is a dirty air filter. Your HVAC system needs the right pressure balance to function properly. There is positive pressure in the supply (air leaving the furnace to warm your home) and negative pressure in the return (air returning to the furnace). When the air filter gets dirty, the fan can’t pull air through the return and out the supply. The restricted airflow causes low pressure on the return side and high pressure on the supply side, causing the duct-work to constrict and create a banging sound.
Air filters with a lower MERV rating allow more air flow, but collect fewer particles, while an air filter with a higher MERV rating traps more particles, but restricts air flow. A very high MERV rating, air won’t be able to flow through the filter, causing banging in the duct-work.
DUCTS:
A more alarming reason your duct-work may be banging is that the ducts were incorrectly sized. Your duct-work needs to be proportionate to the size of your heater. If your heater is too big for your duct-work, it causes pressure imbalances in the supply and the return. These imbalances cause the duct-work to expand and contract, which can sound like banging or popping.
While you should always get to the bottom of banging duct-work, that may cause that is more concerning (and costly) than other potential issues. "If a new system was put in and the banging happens immediately, you need to call a professional to come out and diagnose the problem, as this could be an indicator that the wrong-sized duct-work was installed putting stress on the system and potentially causing it to break." Another time to worry is if you change your air filter and the banging continues, as this may mean there is a bigger issue at hand.
Check each room in your home to make sure your air vents aren't obstructed or closed.
Consult a professional - John's Home Comfort Heating & Cooling, to inspect your HVAC system. While the issue may be as simple as a dirty air filter, it could also be a sign of something more serious. Book a maintenance today. We are close by, Comfort Starts Here!
